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Cohomological invariants of root stacks and admissible double coverings

Published online by Cambridge University Press:  02 November 2021

Andrea Di Lorenzo
Affiliation:
Department of Mathematics, Humboldt-Universität zu Berlin, Berlin, Germany e-mail: dilorena@hu-berlin.de
Roberto Pirisi*
Affiliation:
Dipartimento di Matematica Guido Castelnuovo, Sapienza Università di Roma, Rome, Italy

Abstract

We give a formula for the cohomological invariants of a root stack, which we apply to compute the cohomological invariants and the Brauer group of the compactification of the stacks of hyperelliptic curves given by admissible double coverings.

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Article
Copyright
© Canadian Mathematical Society 2021

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